Mencius said, "There are many arts in teaching. I refuse, as inconsistent with my character, to teach a man, but I am only thereby still teaching him."
CHAPTER 16. HOW A REFUSAL TO TEACH MAY BE TEACHING.
The 亦 in 亦教 is not without its force, but we can hardly express it in a translation. 予不屑之教诲=予不屑教诲之. The 者 carries us on to the next clause for an explanation of what has been said.